#include "freedreno_util.h"
#include "ir3.h"
+#include "ir3_shader.h"
/*
* Copy Propagate:
*/
-
-/* Is it a non-transformative (ie. not type changing) mov? This can
- * also include absneg.s/absneg.f, which for the most part can be
- * treated as a mov (single src argument).
- */
-static bool is_same_type_mov(struct ir3_instruction *instr)
-{
- struct ir3_register *dst = instr->regs[0];
-
- /* mov's that write to a0.x or p0.x are special: */
- if (dst->num == regid(REG_P0, 0))
- return false;
- if (dst->num == regid(REG_A0, 0))
- return false;
-
- if ((instr->category == 1) &&
- (instr->cat1.src_type == instr->cat1.dst_type))
- return true;
- if ((instr->category == 2) && ((instr->opc == OPC_ABSNEG_F) ||
- (instr->opc == OPC_ABSNEG_S)))
- return true;
- return false;
-}
+struct ir3_cp_ctx {
+ struct ir3 *shader;
+ struct ir3_shader_variant *so;
+ unsigned immediate_idx;
+};
/* is it a type preserving mov, with ok flags? */
static bool is_eligible_mov(struct ir3_instruction *instr, bool allow_flags)
struct ir3_register *dst = instr->regs[0];
struct ir3_register *src = instr->regs[1];
struct ir3_instruction *src_instr = ssa(src);
- if (dst->flags & (IR3_REG_ADDR | IR3_REG_RELATIV))
+
+ /* only if mov src is SSA (not const/immed): */
+ if (!src_instr)
+ return false;
+
+ /* no indirect: */
+ if (dst->flags & IR3_REG_RELATIV)
return false;
if (src->flags & IR3_REG_RELATIV)
return false;
+
if (!allow_flags)
if (src->flags & (IR3_REG_FABS | IR3_REG_FNEG |
IR3_REG_SABS | IR3_REG_SNEG | IR3_REG_BNOT))
return false;
- if (!src_instr)
- return false;
+
/* TODO: remove this hack: */
- if (is_meta(src_instr) && (src_instr->opc == OPC_META_FO))
+ if (src_instr->opc == OPC_META_FO)
+ return false;
+ /* TODO: we currently don't handle left/right neighbors
+ * very well when inserting parallel-copies into phi..
+ * to avoid problems don't eliminate a mov coming out
+ * of phi..
+ */
+ if (src_instr->opc == OPC_META_PHI)
return false;
return true;
}
unsigned valid_flags;
flags = cp_flags(flags);
- /* clear flags that are 'ok' */
- switch (instr->category) {
+ /* If destination is indirect, then source cannot be.. at least
+ * I don't think so..
+ */
+ if ((instr->regs[0]->flags & IR3_REG_RELATIV) &&
+ (flags & IR3_REG_RELATIV))
+ return false;
+
+ /* TODO it seems to *mostly* work to cp RELATIV, except we get some
+ * intermittent piglit variable-indexing fails. Newer blob driver
+ * doesn't seem to cp these. Possibly this is hw workaround? Not
+ * sure, but until that is understood better, lets just switch off
+ * cp for indirect src's:
+ */
+ if (flags & IR3_REG_RELATIV)
+ return false;
+
+ switch (opc_cat(instr->opc)) {
case 1:
- valid_flags = IR3_REG_IMMED | IR3_REG_RELATIV;
- if (flags & ~valid_flags)
- return false;
- break;
- case 5:
- /* no flags allowed */
- if (flags)
- return false;
- break;
- case 6:
- valid_flags = IR3_REG_IMMED;
+ valid_flags = IR3_REG_IMMED | IR3_REG_CONST | IR3_REG_RELATIV;
if (flags & ~valid_flags)
return false;
break;
case 4:
/* seems like blob compiler avoids const as src.. */
/* TODO double check if this is still the case on a4xx */
- if (flags & IR3_REG_CONST)
+ if (flags & (IR3_REG_CONST | IR3_REG_IMMED))
return false;
if (flags & (IR3_REG_SABS | IR3_REG_SNEG))
return false;
break;
+ case 5:
+ /* no flags allowed */
+ if (flags)
+ return false;
+ break;
+ case 6:
+ valid_flags = IR3_REG_IMMED;
+ if (flags & ~valid_flags)
+ return false;
+
+ if (flags & IR3_REG_IMMED) {
+ /* doesn't seem like we can have immediate src for store
+ * instructions:
+ *
+ * TODO this restriction could also apply to load instructions,
+ * but for load instructions this arg is the address (and not
+ * really sure any good way to test a hard-coded immed addr src)
+ */
+ if (is_store(instr) && (n == 1))
+ return false;
+
+ /* disallow CP into anything but the SSBO slot argument for
+ * atomics:
+ */
+ if (is_atomic(instr->opc) && (n != 0))
+ return false;
+ }
+
+ break;
}
return true;
/* propagate register flags from src to dst.. negates need special
* handling to cancel each other out.
*/
-static void combine_flags(unsigned *dstflags, unsigned srcflags)
+static void combine_flags(unsigned *dstflags, struct ir3_instruction *src)
{
+ unsigned srcflags = src->regs[1]->flags;
+
/* if what we are combining into already has (abs) flags,
* we can drop (neg) from src:
*/
*dstflags ^= IR3_REG_SNEG;
if (srcflags & IR3_REG_BNOT)
*dstflags ^= IR3_REG_BNOT;
-}
-static struct ir3_instruction * instr_cp(struct ir3_instruction *instr, unsigned *flags);
+ *dstflags &= ~IR3_REG_SSA;
+ *dstflags |= srcflags & IR3_REG_SSA;
+ *dstflags |= srcflags & IR3_REG_CONST;
+ *dstflags |= srcflags & IR3_REG_IMMED;
+ *dstflags |= srcflags & IR3_REG_RELATIV;
+ *dstflags |= srcflags & IR3_REG_ARRAY;
+
+ /* if src of the src is boolean we can drop the (abs) since we know
+ * the source value is already a postitive integer. This cleans
+ * up the absnegs that get inserted when converting between nir and
+ * native boolean (see ir3_b2n/n2b)
+ */
+ struct ir3_instruction *srcsrc = ssa(src->regs[1]);
+ if (srcsrc && is_bool(srcsrc))
+ *dstflags &= ~IR3_REG_SABS;
+}
-/* the "plain" MAD's (ie. the ones that don't shift first src prior to
- * multiply) can swap their first two srcs if src[0] is !CONST and
- * src[1] is CONST:
- */
-static bool is_valid_mad(struct ir3_instruction *instr)
+static struct ir3_register *
+lower_immed(struct ir3_cp_ctx *ctx, struct ir3_register *reg, unsigned new_flags)
{
- return (instr->category == 3) && is_mad(instr->opc);
+ unsigned swiz, idx, i;
+
+ reg = ir3_reg_clone(ctx->shader, reg);
+
+ /* in some cases, there are restrictions on (abs)/(neg) plus const..
+ * so just evaluate those and clear the flags:
+ */
+ if (new_flags & IR3_REG_SABS) {
+ reg->iim_val = abs(reg->iim_val);
+ new_flags &= ~IR3_REG_SABS;
+ }
+
+ if (new_flags & IR3_REG_FABS) {
+ reg->fim_val = fabs(reg->fim_val);
+ new_flags &= ~IR3_REG_FABS;
+ }
+
+ if (new_flags & IR3_REG_SNEG) {
+ reg->iim_val = -reg->iim_val;
+ new_flags &= ~IR3_REG_SNEG;
+ }
+
+ if (new_flags & IR3_REG_FNEG) {
+ reg->fim_val = -reg->fim_val;
+ new_flags &= ~IR3_REG_FNEG;
+ }
+
+ for (i = 0; i < ctx->immediate_idx; i++) {
+ swiz = i % 4;
+ idx = i / 4;
+
+ if (ctx->so->immediates[idx].val[swiz] == reg->uim_val) {
+ break;
+ }
+ }
+
+ if (i == ctx->immediate_idx) {
+ /* need to generate a new immediate: */
+ swiz = i % 4;
+ idx = i / 4;
+ ctx->so->immediates[idx].val[swiz] = reg->uim_val;
+ ctx->so->immediates_count = idx + 1;
+ ctx->immediate_idx++;
+ }
+
+ new_flags &= ~IR3_REG_IMMED;
+ new_flags |= IR3_REG_CONST;
+ reg->flags = new_flags;
+ reg->num = i + (4 * ctx->so->constbase.immediate);
+
+ return reg;
}
/**
* instruction).
*/
static void
-reg_cp(struct ir3_instruction *instr, struct ir3_register *reg, unsigned n)
+reg_cp(struct ir3_cp_ctx *ctx, struct ir3_instruction *instr,
+ struct ir3_register *reg, unsigned n)
{
- unsigned src_flags = 0, new_flags;
- struct ir3_instruction *src_instr;
+ struct ir3_instruction *src = ssa(reg);
- if (is_meta(instr)) {
- /* meta instructions cannot fold up register
- * flags.. they are usually src for texture
- * fetch, etc, where we cannot specify abs/neg
- */
- reg->instr = instr_cp(reg->instr, NULL);
+ /* don't propagate copies into a PHI, since we don't know if the
+ * src block executed:
+ */
+ if (instr->opc == OPC_META_PHI)
return;
- }
- src_instr = instr_cp(reg->instr, &src_flags);
+ if (is_eligible_mov(src, true)) {
+ /* simple case, no immed/const/relativ, only mov's w/ ssa src: */
+ struct ir3_register *src_reg = src->regs[1];
+ unsigned new_flags = reg->flags;
- new_flags = reg->flags;
- combine_flags(&new_flags, src_flags);
+ combine_flags(&new_flags, src);
- reg->flags = new_flags;
- reg->instr = src_instr;
-
- if (!valid_flags(instr, n, reg->flags)) {
- /* insert an absneg.f */
- if (reg->flags & (IR3_REG_SNEG | IR3_REG_SABS | IR3_REG_BNOT)) {
- debug_assert(!(reg->flags & (IR3_REG_FNEG | IR3_REG_FABS)));
- reg->instr = ir3_ABSNEG_S(instr->block,
- reg->instr, cp_flags(src_flags));
- } else {
- debug_assert(!(reg->flags & (IR3_REG_SNEG | IR3_REG_SABS | IR3_REG_BNOT)));
- reg->instr = ir3_ABSNEG_F(instr->block,
- reg->instr, cp_flags(src_flags));
+ if (valid_flags(instr, n, new_flags)) {
+ if (new_flags & IR3_REG_ARRAY) {
+ debug_assert(!(reg->flags & IR3_REG_ARRAY));
+ reg->array = src_reg->array;
+ }
+ reg->flags = new_flags;
+ reg->instr = ssa(src_reg);
}
- reg->flags &= ~cp_flags(src_flags);
- debug_assert(valid_flags(instr, n, reg->flags));
- /* send it through instr_cp() again since
- * the absneg src might be a mov from const
- * that could be cleaned up:
- */
- reg->instr = instr_cp(reg->instr, NULL);
- return;
- }
- if (is_same_type_mov(reg->instr)) {
- struct ir3_register *src_reg = reg->instr->regs[1];
- unsigned new_flags = src_reg->flags;
+ src = ssa(reg); /* could be null for IR3_REG_ARRAY case */
+ if (!src)
+ return;
+ } else if (is_same_type_mov(src) &&
+ /* cannot collapse const/immed/etc into meta instrs: */
+ !is_meta(instr)) {
+ /* immed/const/etc cases, which require some special handling: */
+ struct ir3_register *src_reg = src->regs[1];
+ unsigned new_flags = reg->flags;
- combine_flags(&new_flags, reg->flags);
+ combine_flags(&new_flags, src);
if (!valid_flags(instr, n, new_flags)) {
+ /* See if lowering an immediate to const would help. */
+ if (valid_flags(instr, n, (new_flags & ~IR3_REG_IMMED) | IR3_REG_CONST)) {
+ debug_assert(new_flags & IR3_REG_IMMED);
+ instr->regs[n + 1] = lower_immed(ctx, src_reg, new_flags);
+ return;
+ }
+
/* special case for "normal" mad instructions, we can
* try swapping the first two args if that fits better.
+ *
+ * the "plain" MAD's (ie. the ones that don't shift first
+ * src prior to multiply) can swap their first two srcs if
+ * src[0] is !CONST and src[1] is CONST:
*/
- if ((n == 1) && is_valid_mad(instr) &&
+ if ((n == 1) && is_mad(instr->opc) &&
!(instr->regs[0 + 1]->flags & (IR3_REG_CONST | IR3_REG_RELATIV)) &&
valid_flags(instr, 0, new_flags)) {
/* swap src[0] and src[1]: */
conflicts(instr->address, reg->instr->address))
return;
+ /* This seems to be a hw bug, or something where the timings
+ * just somehow don't work out. This restriction may only
+ * apply if the first src is also CONST.
+ */
+ if ((opc_cat(instr->opc) == 3) && (n == 2) &&
+ (src_reg->flags & IR3_REG_RELATIV) &&
+ (src_reg->array.offset == 0))
+ return;
+
+ src_reg = ir3_reg_clone(instr->block->shader, src_reg);
src_reg->flags = new_flags;
instr->regs[n+1] = src_reg;
if (src_reg->flags & IR3_REG_RELATIV)
- instr->address = reg->instr->address;
+ ir3_instr_set_address(instr, reg->instr->address);
return;
}
if ((src_reg->flags & IR3_REG_RELATIV) &&
!conflicts(instr->address, reg->instr->address)) {
+ src_reg = ir3_reg_clone(instr->block->shader, src_reg);
src_reg->flags = new_flags;
instr->regs[n+1] = src_reg;
- instr->address = reg->instr->address;
+ ir3_instr_set_address(instr, reg->instr->address);
return;
}
if (src_reg->flags & IR3_REG_IMMED) {
int32_t iim_val = src_reg->iim_val;
- debug_assert((instr->category == 1) ||
- (instr->category == 6) ||
- ((instr->category == 2) &&
- ir3_cat2_int(instr->opc)));
+ debug_assert((opc_cat(instr->opc) == 1) ||
+ (opc_cat(instr->opc) == 6) ||
+ ir3_cat2_int(instr->opc));
if (new_flags & IR3_REG_SABS)
iim_val = abs(iim_val);
if (new_flags & IR3_REG_BNOT)
iim_val = ~iim_val;
- if (!(iim_val & ~0x3ff)) {
+ /* other than category 1 (mov) we can only encode up to 10 bits: */
+ if ((instr->opc == OPC_MOV) ||
+ !((iim_val & ~0x3ff) && (-iim_val & ~0x3ff))) {
new_flags &= ~(IR3_REG_SABS | IR3_REG_SNEG | IR3_REG_BNOT);
+ src_reg = ir3_reg_clone(instr->block->shader, src_reg);
src_reg->flags = new_flags;
src_reg->iim_val = iim_val;
instr->regs[n+1] = src_reg;
+ } else if (valid_flags(instr, n, (new_flags & ~IR3_REG_IMMED) | IR3_REG_CONST)) {
+ /* See if lowering an immediate to const would help. */
+ instr->regs[n+1] = lower_immed(ctx, src_reg, new_flags);
}
return;
}
}
-/**
- * Given an SSA src (instruction), return the one with extraneous
- * mov's removed, ie, for (to copy NIR syntax):
- *
- * vec1 ssa1 = fadd <something>, <somethingelse>
- * vec1 ssa2 = fabs ssa1
- * vec1 ssa3 = fneg ssa1
- *
- * then calling instr_cp(ssa3, &flags) would return ssa1 with
- * (IR3_REG_ABS | IR3_REG_NEGATE) in flags. If flags is NULL,
- * then disallow eliminating copies which would require flag
- * propagation (for example, we cannot propagate abs/neg into
- * an output).
+/* Handle special case of eliminating output mov, and similar cases where
+ * there isn't a normal "consuming" instruction. In this case we cannot
+ * collapse flags (ie. output mov from const, or w/ abs/neg flags, cannot
+ * be eliminated)
*/
static struct ir3_instruction *
-instr_cp(struct ir3_instruction *instr, unsigned *flags)
+eliminate_output_mov(struct ir3_instruction *instr)
{
- struct ir3_register *reg;
-
- /* stay within the block.. don't try to operate across
- * basic block boundaries or we'll have problems when
- * dealing with multiple basic blocks:
- */
- if (is_meta(instr) && (instr->opc == OPC_META_INPUT))
- return instr;
-
- if (is_eligible_mov(instr, !!flags)) {
+ if (is_eligible_mov(instr, false)) {
struct ir3_register *reg = instr->regs[1];
- struct ir3_instruction *src_instr = ssa(reg);
- if (flags)
- combine_flags(flags, reg->flags);
- return instr_cp(src_instr, flags);
+ if (!(reg->flags & IR3_REG_ARRAY)) {
+ struct ir3_instruction *src_instr = ssa(reg);
+ debug_assert(src_instr);
+ return src_instr;
+ }
}
+ return instr;
+}
+
+/**
+ * Find instruction src's which are mov's that can be collapsed, replacing
+ * the mov dst with the mov src
+ */
+static void
+instr_cp(struct ir3_cp_ctx *ctx, struct ir3_instruction *instr)
+{
+ struct ir3_register *reg;
+
+ if (instr->regs_count == 0)
+ return;
- /* Check termination condition before walking children (rather
- * than before checking eligible-mov). A mov instruction may
- * appear as ssa-src for multiple other instructions, and we
- * want to consider it for removal for each, rather than just
- * the first one. (But regardless of how many places it shows
- * up as a src, we only need to recursively walk the children
- * once.)
- */
if (ir3_instr_check_mark(instr))
- return instr;
+ return;
/* walk down the graph from each src: */
foreach_src_n(reg, n, instr) {
- if (!(reg->flags & IR3_REG_SSA))
+ struct ir3_instruction *src = ssa(reg);
+
+ if (!src)
continue;
- reg_cp(instr, reg, n);
+ instr_cp(ctx, src);
+
+ /* TODO non-indirect access we could figure out which register
+ * we actually want and allow cp..
+ */
+ if (reg->flags & IR3_REG_ARRAY)
+ continue;
+
+ reg_cp(ctx, instr, reg, n);
+ }
+
+ if (instr->regs[0]->flags & IR3_REG_ARRAY) {
+ struct ir3_instruction *src = ssa(instr->regs[0]);
+ if (src)
+ instr_cp(ctx, src);
}
- if (instr->address)
- instr->address = instr_cp(instr->address, NULL);
+ if (instr->address) {
+ instr_cp(ctx, instr->address);
+ ir3_instr_set_address(instr, eliminate_output_mov(instr->address));
+ }
- return instr;
+ /* we can end up with extra cmps.s from frontend, which uses a
+ *
+ * cmps.s p0.x, cond, 0
+ *
+ * as a way to mov into the predicate register. But frequently 'cond'
+ * is itself a cmps.s/cmps.f/cmps.u. So detect this special case and
+ * just re-write the instruction writing predicate register to get rid
+ * of the double cmps.
+ */
+ if ((instr->opc == OPC_CMPS_S) &&
+ (instr->regs[0]->num == regid(REG_P0, 0)) &&
+ ssa(instr->regs[1]) &&
+ (instr->regs[2]->flags & IR3_REG_IMMED) &&
+ (instr->regs[2]->iim_val == 0)) {
+ struct ir3_instruction *cond = ssa(instr->regs[1]);
+ switch (cond->opc) {
+ case OPC_CMPS_S:
+ case OPC_CMPS_F:
+ case OPC_CMPS_U:
+ instr->opc = cond->opc;
+ instr->flags = cond->flags;
+ instr->cat2 = cond->cat2;
+ instr->address = cond->address;
+ instr->regs[1] = cond->regs[1];
+ instr->regs[2] = cond->regs[2];
+ break;
+ default:
+ break;
+ }
+ }
}
-static void block_cp(struct ir3_block *block)
+void
+ir3_cp(struct ir3 *ir, struct ir3_shader_variant *so)
{
- unsigned i;
+ struct ir3_cp_ctx ctx = {
+ .shader = ir,
+ .so = so,
+ };
- for (i = 0; i < block->noutputs; i++) {
- if (block->outputs[i]) {
- struct ir3_instruction *out =
- instr_cp(block->outputs[i], NULL);
+ ir3_clear_mark(ir);
- block->outputs[i] = out;
+ for (unsigned i = 0; i < ir->noutputs; i++) {
+ if (ir->outputs[i]) {
+ instr_cp(&ctx, ir->outputs[i]);
+ ir->outputs[i] = eliminate_output_mov(ir->outputs[i]);
}
}
-}
-void ir3_block_cp(struct ir3_block *block)
-{
- ir3_clear_mark(block->shader);
- block_cp(block);
+ list_for_each_entry (struct ir3_block, block, &ir->block_list, node) {
+ if (block->condition) {
+ instr_cp(&ctx, block->condition);
+ block->condition = eliminate_output_mov(block->condition);
+ }
+
+ for (unsigned i = 0; i < block->keeps_count; i++) {
+ instr_cp(&ctx, block->keeps[i]);
+ block->keeps[i] = eliminate_output_mov(block->keeps[i]);
+ }
+ }
}